Flybarless conversion

[ghostflyer]

Is it possible to convert a flybar head just by removing the flybar and associated control linkage and feed the blades directly from the swash plate? Of course phasing would need to be adjusted. Head like the aluminium upgrade for the Raptor would allow that since the phase ring is separate from the hub.

Anyone ever tried???

Thanks,
David

[Motions]

That's basically how it's done. However, there are other details to take note of. You would need to install a follower on the swash and you would need an electronic stabilization system like the Mikado V-Bar since you have removed the mechanical gyroscopic system (flybar).

[ghostflyer]

What about the blades?
In Dr Tim column, he mentionned the blades need to be heavier. Is this really a must?
I am thinking about converting my old shuttle to flybarless. May not be easy to find special blade for a .30 size heli.

[Motions]

Heavy blades are not a must. It depends on the application. If your using it for a scale project, heavy blades will help with stability. In a 3D application, lighter blades would be better. But if your using an electronic gyro system to replace the flybar, it can be tweaked to get the feel you want.

[Dr.Tim]

That's right on the money .. in Scale we need the heavy blades because of the lower headspeeds and smooth flying required for comp. For 3D things get a little wilder! :) An electronik mixer is not needed for 2 blade or even 3 or 4 blade if your radio allows phazing. The mixer is a good idea to simplify the setup and add the phazing for you. The Helitronix even allows for the use of gyros if need be.

Dr.Tim

[Rappy1]

Hey Dr tim
I see you say that you use slower head speeds for scale flying, what RPM do you tend to run at. Just as a idea for my longranger.

[Dr.Tim]

My Super Puma with the Vario Benzin mechanics swinging a 4 blade head runs 1250 .. my Cobra with the Jakadofsky Turbine and a 2 blade flybarless runs 1200 (875mm blades)

Dr.Tim

[ghostflyer]

I would assume the head speed depend also on the heli size. So slow for a Raptor will be different than for a larger heli like your Puma.

Also, I remember reading about pitching tendency in forward flight. What is the cause and how is it affected by head speed and blade weight?

[Dr.Tim]

In forward flight you will have to learn to control altitude with pitch not elevator control. The problem is the faster you go the more the helicopter will want to climb .. the solution is to back off on Pitch. If you use elevator to push the nose down the helicopter will simply try to climb as it speeds up.

Dr.Tim

[rc heli crazy]

I would assume the head speed depend also on the heli size. So slow for a Raptor will be different than for a larger heli like your Puma.

Also, I remember reading about pitching tendency in forward flight. What is the cause and how is it affected by head speed and blade weight?
here is a pumahttp://www.youtube.com/watch?v=3F2k-GWKW-w&mode=related&search= :eek:

[ghostflyer]

Dr Tim,
Why is it different for flybarless heli? Is it due to the effect of the coning of the blade that is not compensated for by the flybar?

David

[Dr.Tim]

The question should be ... Is it different for a Model Helicopter .... The Flybar is a Dampener for the rotorhead. It acts as a gyro to smooth out how the helicopter reacts. Us Scale guys use Heavy Paddles and or heavy blades to get that smooth scale flight were the 3D and FAI guys use Light paddles and or lighter blades for quicker response. It all depends on your flying style. .. I prefer flybarless and now with all these Electronic devises it makes it that much easier ... Maybe one day I can tell you more about the V-Stabi system .. I have tried the Vario multiblade Gyro and the Helitronix systems with success.
Dr.Tim

[demulder7]

Searching about flybarless and all the pros it may have I didn´t liked the idea of spending at least 400usd on an stabilization system. But I found this video, in which there´s no stabilization system and still the heli is flying

http://es.youtube.com/watch?v=ez_5fWHkpKI

and this one, how to go flybarless

http://es.youtube.com/watch?v=6d_3odKx8Mg&feature=related

in this videos the heli seems to be ok, I´m going to try fly my trex 450 without stabilization sistem

I´ll keep you informed

Dan

[demulder7]

This are some photos about my modification

[Br3tt]

Great thread!

[blax1]

I´ll keep you informed

Dan

Looking forward to that, very interesting and welcome. :)

[demulder7]

Hi, everybody

This afternoon Í did the first flight, the heli was very touchy, so I use exponential to compensate that. I had to use 60% expo, because I leave the alieron and elevator throws as I had them before.

The speed of the ciclic is scary, is amazing, in the video, there´s one part in which I move the alierons hard, well, thats only half of my stick posible movement. It stands for about 30% of the posible alieron movement.

here the vid, hope it´s helpful

http://es.youtube.com/watch?v=uWN6kNpndhI

does it seems unstable?

hope you enjoy it

Dan

pd

In some weeks after flying this one more i´ll try this on my 600N,

[blax1]

Nice vid- Daniel, I can see what you are saying about the cyclic, she just wants to dance :D Congratulation's, the Flybarless Rex looks very interesting, your obviously a very accomplished pilot as well, nice flying :cool:

Have fun......... :)

[heli-cuzz]

Great job on the flybarless. You saved a ton of money not using a stabilization system. :cool:

[demulder7]

Yesterday I continued flying the heli, and I was amazed how well it performed. But when I fly it on windy conditions, the heli is very strange and challenging. It tries to climb in forward and backward flight, But if I stop it hovers very stable.

I´ll continue doing tests on it, then I´ll make the descision about making the conversion on the 600n

Thank you in the next post I´ll post an other video show this fenomenom

thank you

Dan

[Shawn K]

Yesterday I continued flying the heli, and I was amazed how well it performed. But when I fly it on windy conditions, the heli is very strange and challenging. It tries to climb in forward and backward flight, But if I stop it hovers very stable.

Par for the course. Flying flybarless is a very different discipline. That's why extra points are awarded in scale competition for using a flybarless head during the flight phase.

With practice, you'll learn to adapt and overcome, just like you've done with everything else. Don't lean on electronic gimmicks... just be a man and wrestle that bird into compliance! ;) :D

[schluterdude]

my schluter has an addendum to the instructions that says for scale flight, slimply remove the flybar, and replace it with a blind axle. one of these days, when i finally get around to a scale project, i was thinking of doing just that. this thread has helped out as far issues concerning a conversion. great threat man!